ABSTRACT
Cyermethrin, a type II synthetic pyrethroid insecticide, was evaluated through assessment of the behavioral development of F1-progeny of mice. Groups each of 30 male and 30 female ICR (CD-l) mice, as F0-generation, were given 0, 2.5, 5, and 10mg/kg/day cypermethrin in corn oil orally for 4 weeks/5 days in a week before mating. Behavioral endpoints of motor reflexes, motor coordination, and activity were evaluated in F1-progeny. Clinical signs of toxicity including salivation, hyperactivity, and tremors which attributed to cypermethrin were observed in the F0-mice treated with 10mg/kg/day. A significant delay in the development of pinna detachment, down appearance, and eye opening of 48, 59, and 27 pups (47, 64, and 39%, respectively) was observed in the high dose group. Reduction of body weight became significantly evident only for F0-females either during treatment or gestation and lactation periods for the high dose group. Significant differences in the development of reflexes, swimming ability, and open-field activity were evident in the offspring for the 10mg/kg/day dose group compared to the control group. These results show that cypermethrin at dose level of 10mg/kg/day can induce a significant risk to the offspring following treatment of F0-mice before mating. The NOAEL obtained in this study for the effects of cypermethrin on the development of the F1-progeny is 5mg/kg/day.
Subject(s)
Behavior, Animal/drug effects , Insecticides/toxicity , Pyrethrins/toxicity , Administration, Oral , Animals , Body Weight/drug effects , Dose-Response Relationship, Drug , Ear, External/drug effects , Ear, External/growth & development , Eye/drug effects , Eye/growth & development , Female , Insecticides/administration & dosage , Male , Maternal Exposure , Mice , Mice, Inbred ICR , Motor Activity/drug effects , No-Observed-Adverse-Effect Level , Paternal Exposure , Pyrethrins/administration & dosage , Reflex/drug effects , Risk Assessment , Social BehaviorABSTRACT
The effect of organophosphate insecticide dimethoate at three dosage levels (7, 15, and 28 mg/kg/day) on male reproduction in mice was studied. Dimethoate was given orally by gavage to male mice for 20 days before mating with untreated females. Signs of cholinergic effects were observed in the 15 and 28 mg/kg/day treated groups. Brain and skeletal muscle acetylcholinesterase activities were inhibited in both the middle and high dose groups. Dimethoate was associated with a decreased number of implantations and live fetuses, and an increased number of dead and early resorptions at 28 mg/kg/day treated group. The percent morphologically normal spermatozoa were unaffected in any of dose groups. However, sperm production and percent motile sperm were decreased in the 15 and 28 mg/kg/day treated groups compared to the control. Histological changes in testis were observed in the middle and high treated groups. The current study demonstrated the adverse effects of dimethoate on the reproductive performance of male mice and pregnancy outcomes following mating with untreated female mice at dose levels of 15 and 28 mg/kg/day. The No Observed Effect Level (NOEL) in the present study for reproductive performance was 7 mg/kg/day.
Subject(s)
Cholinesterase Inhibitors/toxicity , Dimethoate/toxicity , Insecticides/toxicity , Reproduction/drug effects , Testis/drug effects , Acetylcholinesterase/metabolism , Administration, Oral , Animals , Brain/drug effects , Brain/enzymology , Dose-Response Relationship, Drug , Embryo Implantation/drug effects , Female , Fetal Death/chemically induced , Fetal Resorption/chemically induced , Litter Size/drug effects , Male , Mice , Mice, Inbred ICR , Muscle, Skeletal/drug effects , Muscle, Skeletal/enzymology , No-Observed-Adverse-Effect Level , Sperm Count , Sperm Motility/drug effects , Spermatozoa/cytology , Spermatozoa/drug effects , Testis/pathologyABSTRACT
Permethrin, a type I synthetic pyrethroid insecticide, was evaluated through assessment of the behavioral development of F1 progeny of mice. Groups each of 30 male and 30 female ICR (CD-1) mice, as F0-generation, were given 0, 4.9, 9.8, and 19.6 mg/kg/d permethrin by gavage for 4 weeks before mating. Behavioral endpoints of motor reflexes, motor coordination, and activity were evaluated in F1 progeny. Clinical signs of toxicity including salivation, hyperactivity, and liquid feces which attributed to permethrin were observed in the F0-mice treated with 9.8 and 19.6 mg/kg/d. Reduction of body weight became evident only during gestation and lactation periods for the middle and high dose groups. Significant differences in the development of reflexes, swimming ability, and open field activity were evident in the offspring for the 9.8 and 19.6 mg/kg/d dose groups compared to the control group. These results show that permethrin at dose levels of 9.8 and 19.6 mg/kg/d can induce a significant risk to the offspring following treatment of F0-mice before mating. The NOEL obtained in this study for the effects of permethrin on the development of the F1-progeny is 4.9 mg/kg/d.
